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    <script>
        var uniquePaths = function (m, n) {
          let dp = new Array(m).fill().map(() => new Array(n).fill(0))
          for (let i = 0; i < m; i++) {
            dp[i][0] = 1
          }
          for (let j = 0; j < n; j++) {
            dp[0][j] = 1
          }
          for (let i = 1; i < m; i++) {
            for (let j = 1; j < n; j++) {
              dp[i][j] = dp[i - 1][j] + dp[i][j - 1]
            }
          }
          return dp[m - 1][n - 1]
        }
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